Engine primer



A. L. PARKER ENGINE PRIMER Feb. 16, 1943.

Filed March 5; 1941 m w M W 2 f Patented Feb. 16, 1943 UNITEDsrerssrarer OFFICE ENGINljl PRIMER Arthur L. Parker, Cleveland, OhioApplication March 8, 1941, Serial No. 381,553

' 9 Claims. I (01. 103 2 The present invention relates to new and usefulimprovements in a device for dispensing fluid to one or more selectedpoints, and more particularly to improvements in a device of this typewhich is adapted to be used as a primer for engines.

In the prior patents of Arthur L. Parker, No. 1,934,878, dated November14, 1933, No. 1,942,255, dated January 2, 1934, and No. 2,185,564, datedJanuary 2, 1940, there are shown engine primers:

of this general type and the present invention relates to certain novelimprovements in connection therewith. The invention is illustratedparticularly in connection with the type of primer shown in the ParkerPatent No. 2,185,564 al--' though it is to be clearly understood thatother types of primers may be employed with the improvements of thepresent invention. This type of primer is in the form of a pump whichincludes a pump barrel or casing within which a piston is reciprocable.There is also provided a valve housing associated with the casin and adistributing valve is disposed within the valve housing. The valvehousing has an inlet connection and one or more outlet connections Whichare the end of its stroke whereby to permit rotation of the valve uponrotation of the piston in order to properly-position the valve for anyselected point of distribution of the fluid. While the piston and valveare engaged, limited axial movement of the piston relative to the valveis permitted in order to effect locking of the piston and the valve in aposition closing the outlet port or ports and preventing distribution ofthe fluid. In order to release the piston from this locked position, itis necessary to effect relative movement of the piston with respect tothe valve and this movement of the piston includes an initial axialmovement tending to compress any fluid which is trapped within the pumpcasing.

A primer of this type maybe conveniently used in various installations,as for instance, in airplane installations, Where fuel is withdrawn bythe primer from a source of supply, preferably through a strainer, andthen forced into the en.- gine for facilitating the starting thereof.The

primer may be installed with the inlet line connected to either the lowor the high pressure side of the power fuel pump and it is, of course,desirable to install the primer so that a minimum movement of strokes ofthe piston is necessary in order to force fuel into the engine. Wherethe primer is mounted a substantial distance above the source of supplyor strainer, the increased head will often cause some of the fluid todrain back so that a number of strokes of the piston are necessarybefore the inlet line to the primer is filled and the fuel forced to theengine. In order to overcome this difliculty, the primer is sometimesinstalled with the inlet line thereof connected to the pressure side ofthe power pump which pumps fuel under relatively low pressure (15 or 20lbs. per sq. in). After an initial starting of the engine, the powerpump will tend to force fuel into the primerinlet line and even when theprimer is shut off, the power pump may continue to exert sufficientpressure on the primer inlet line so as to unseat the check valve in theinlet port. This action will result in the maintenance of this samepressure within the primer itself and when the engine and power pump arestopped, the pump casing will be full of fuel'which will be trappedtherein by the check valve at the inlet port. Since it is necessary toforce the piston axially in the direction of compression for releasingthe locking means, this movement is often prevented because of therelative incompressibility of the fuel which is trapped within the pumpcasing. When this occurs, it is impossible to release the piston fromits locked position and such a condition may also result when the primeris connected to the low pressure side of the power pump.

An object of the present'invention is to provide a primer of the abovetype which is constructed and arranged in such a manner as to permitsufficient movement of the piston under all conditions to release thepiston from its locked position.

A further object of the invention is to provide a primer of the abovetype wherein means are provided for'permitting displacement of the fluidwithin the pump casing in order to permit the piston to be shifted awayfrom its locked position.

A still further object of the invention is to provide a primer of theabove type having a closed chamber which is compressible to permitdisplacement of the fluid within the pump casing in order to permit thepiston to be released from its locked position.

The above and other objects of the invention member 24.

will in part be obvious and will be hereinafter more fully pointed out.1

In the accompanying drawing:

Figure 1 is a longitudinal sectional view through the primer and showingthe piston and valve in a position for pumping fluid therethrough.

Figure 2 is an enlarged fragmentary view, in longitudinal section,showing the position of the piston and its associated parts whenreleased from its locked position.

Figure 3 is a reduced transverse sectional view through the inner end ofthe piston and casing.

Figure 4 is a detail sectional view showing the locking slot in thecasing.

The construction and operation of the primer is substantially identicalto the primer shown in the Parker aforesaid Patent No. 2,185,564 but abrief description will be included herein. Referring more in detail tothe accompanying drawing, the pump casing II) is illustrated asincluding a flange portion II by which the primer may be secured to asuitable support, as for instance, the cowl of an airplane. The outerend of the casing I includes an outwardly offset sleeve portion I2 whichis externally threaded and the opposite end of the casing is outwardlyoffset to provide an internal chamber I3. A valve housing I4 isillustrated as being integral with the casing but this housing may beformed separate therefrom, if so desired. The valve housing includes aninlet connection I5 and one or more outlet connections I6, I! throughwhich the fuel may be distributed. The piston I8 is mounted within thepump barrel or casing with a close sliding fit and the outer end of thepiston -may be provided with a handle I9. An annular cap 20 threadedlyengages the skirt portion I2 on the casing and also engages a packingfollower 2| which is adapted to compress the packing 22 in order toprovide a fluid-tightseal.

,The valve housing. I4 is provided with a tapered seat in which islocated a conical valve member 23 which is pressed against the seat by aspring 24 having the inner end thereof abutting against the valve memberand having the outer end thereof bearing against an abutment The bottomof the valve housing is closed by a cap 25 which is provided with anaperture 26 therethrough. A diaphragm 21 extends across the aperture 26within the cap 25 and is thus subject to atmospheric pressure.

The valve member is provided with a centrally located port 28 which isin communication with the chamber I3 and there is also provided a radialport 29 which is adapted to selectively register with outlet ports incommunication with the outlet connections I6 or I1. The inner end of theport 28 is provided with a valve seat with which a ball check valve 36is adapted to cooperate for controlling the passage of fluid. The ball30 is yieldingly pressed against the seat by a plunger 3| which isrecessed to house a spring 32 having the inner end thereof bearingagainst the plunger and having the outer end thereof bearing against thediaphragm 21. The inlet connection I5 is provided with a valve seatformed in the inner end of an annular insert 33 and a ball check valve34 is adapted to cooperate therewith. A passage 35 afiords communicationbetween the chamber I3 and the inlet connection I5.

The piston I8 is provided with a longitudinal recess 36 and the open endof the recess is closed by a plug '31 which is secured to the piston bya pin 38 or the like. A key 39 extends across the inner end of thepiston and through a' slot in the plug 31 and is secured thereto by thepin 38. The wall of the pump casing I 0 is 5 provided withlongitudinally extending recesses or keyways 40, 40a which aresymmetrically positioned with respect to the outlet connection I6, I1and with which a projection or looking lug M on the key 39 is adapted tocooperate.

Between the keyways 40, 400., there is provided a locking recess 42 intowhich the lug M is adapted to extend upon proper manipulation of thepiston in order to lock the same. The extended end of the plug 31 isprovided with an annular shoulder portion 43 and also with a slot intowhich a transversely extending projection or key 44 on the valve memberis adapted to extend. This slot and key connection provide means wherebythe valve member can be rotated upon rotation of the piston when thepiston reaches the inner end of its stroke. A cup member 45 is mountedon the extended end of the plug 31 by means of an inwardly extendingflange and the opposite end of the cup member is provided with anoutwardly extending flange 46. A spring 4! surrounds the cup member andhas one end thereof bearing on the flange 46 and the opposite endthereof bearing against the inner end of the piston. The spring and thecup member move with the piston during reciprocation thereof and theparts are so dimensioned that when the piston is moved inwardly duringcompression, the cup member will contact with the bottom wall of thechamber I3 and at this time, the extended end of the plug 31 becomesengaged with the key 44 on the valve member and further inward movementof the piston will compress the spring 41 and move the lug 4I out of thekeyway in the side wall 40 of the pump casing. Thus, the keyways 40 or40a are adapted to be aligned with the lug 4| so as to permit pumpingreciprocation of the piston. When it is desired to turn the valve to anoff position, the piston can be rotated so that the lug M will becomealigned with the locking recess 42 and when pressure on the piston isreleased, the spring 41 will force the piston outwardly so that thepiston or valve member Will be locked with the lug 44 engaged in therecess 42.

The plug 31 is provided with a relatively small aperture 48 therethroughand this aperture provides restricted communication between the chamberI3 and the recess 36. A compressible chamber is disposed in the recess36 within the inner end of the plug 31. This compressible chamber isillustrated as including a tubular bag 49 having a flexible wall portionand the end of the bag is closed by a plug 50. The wall portion of thebag is secured in sealed relationship with the closing plug 50 by meansof a clamping ring 5| or the like. The bag is filled with air or otherfluid which is more compressible than the fuel or other fluid to bepumped by the primer.

- The compressible bag substantially fills the recess 36 in the pistonI8 although it is illustrated as being slightly spaced from the wallsthereof so that the fuel will gain access to the recess '36 through therestricted aperture 48.

In operation, the ,piston is forced inwardly so that the locking lugpasses out of the locking recess 42 and the piston may then be turnedinto alignment with one of the keyways 40, 40a. As illustrated in Figure1, the lug 4| is disposed in v the keyway 40 and the valve port 29 is incommunication with the outlet line It. In this position of the parts,the piston can be manually reciprocated by means of the handle 19. Onthe outward suction stroke of the pistons I8, fuel will be drawn fromthe inlet line l past the check valve 34 and into the chamber l3 and thepiston casing through the port 35. Upon inward movement of the pistonl8, the check valve 34 will be closed and the ball check valve 30 willbe opened so that fuel is forced through the port 39 into the outletline I6 from which the fuel is directed to the desired location. Duringpriming, any suction pull on the outlet connection from the engine willcreate a vacuum in the recessbeneath the plunger 3| by means of the port3la therethrough. The diaphragm being subject to atmospheric pressure,will shift inwardly so as to increase the tension of the spring 32 and.thus tightly seat the ball check valve 311. After initial priming, theengine is started and the primer is turned to an off position, that is,the piston 18 is forced inwardly so as to withdraw the lug 4| from therecess 40 and the piston is then rotated so that the lug 4| can bepositioned within the lock recess 42. In this locked position of theprimer, the port 29 will be shifted with the valve member 23 so that itis out oi register with the outlet lines.

As previously indicated, the piston casing becomes completely filledwith fuel so that a subsequent release of the locking means for thepiston and valve is rendered difficult or impossible by reason of thefact that the piston must be moved inwardly in the direction of compression for releasing the lug 4[ from the locking recess 42. For instance,where the inlet line [5 is connected to the high pressure side of thepower pump, continued operation of the power pump by the engine willtend to transmit the pressure of the power pump through the inlet lineand against the check valve 34. When this pressure is sufficient toovercome the close tendency of the check valve 34, the pressure will betransmitted to the fluid filling the chamber [3 and the recess 36. Then,when the engine is stopped, the check valve 34 prevents release of thisadditional pressure so that it may be impossible to shift the piston l8inwardly to release the locking device. However, the provision of thecompressible chamber 49 permits the piston to be moved inwardly at leasta suflicient distance to release the lug 4| from the locking recess 42.During this inward forcing of the piston, the compressible bag 49 willbe forced inwardly in some manner, as shown in Figure 2,.

to compress the air therein and permit a corresponding displacement ofthe relatively incompressible fuel so as to facilitate unlocking of thepiston and valve member.

From the foregoing description, it will be seen.

that the present invention provides an improved and highly eificientengine primer assembly wherein manual operation of the primer is greatlyfacilitated. Furthermore, the present invention provides a primer whichcan be manually operated under all conditions. Thus, the compressibleair bag within the piston operates as a safety device to permitdisplacement of any trapped fluid in order to permit release of thepiston and valve from locked position. The compressible fluid within thebag is such as to permit downward movement of the piston from a lockedposition by permitting the necessary displacement of fluid which istrapped within the casing.

While one form of the invention has been shown for purposes ofillustration, it is to be clearly understood that various changes in thedetails of construction and arrangement of parts may be made withoutdeparting from the scope of the invention as set forth in the appendedclaims.

I claim:

1. A fluid dispensing device comprising a pump casing having areciprocating piston therein, a distributing valve associated with thecasing for controlling distribution of the fluid, means operable to"provide a releasable connection between the piston and the valve nearthe end of the compression stroke of the piston whereby rotation of thepiston will effect rotation of the valve to different set positions,locking means for preventing rotation of the connected piston and valvefrom an inoperative position preventing distribution of fluid and saidlocking means being releasable upon initial movement of the piston inthe direction of compression, and means providing a variable chamberassociated with the dispensing device and responsive to displacement offluid within the casing for permitting displacement of the fluid in thecasing upon movement of the piston away from its locked position wherebyto facilitate release of the locking means.

2. A fluid dispensing device comprising a pump casing having a,reciprocating piston therein, a distributing valve associated with thecasing for controlling distribution of the fluid, means operable toprovide a releasable connection between the piston and the valve nearthe end of the compression stroke of the piston whereby rotation of thepiston will effect rotation of the valve to different set positions,locking means for preventing rotation of the connected piston and valvefrom an inoperative position preventing distribution of fluid and saidlocking means being releasable upon initial movement of the piston inthe direction of compression, and means providing a closed compressiblechamber located within the dispensing device and responsive todisplacement of fluid therein for permitting displacement of the fluidin the casing upon movement of the piston away from its locked positionwhereby to facilitate release of the locking means.

3. A fluid dispensing device comprising a pump casing having areciprocating piston therein, a distributing valve associated with thecasing for controlling distribution of the fluid, means operable toprovide a releasable connection between the piston and the valve nearthe end of the compression stroke of the piston whereby rotation of thepiston will effect rotation of the valve to different set positions,locking means for preventing rotation of the connected piston and valvefrom an inoperative position prevent- 4. A fluid dispensing devicecomprising a pump casing having a reciprocating piston therein, adistributing valve associated with the casing for controllingdistribution of the fluid, means operable to provide a releasableconnection between the piston and the valve near the end of thecompression stroke of the piston whereby rotation of the piston willeffect rotation of the valve to different set positions, locking meansfor preventing rotation of the connected piston and valve from aninoperative position preventing distribution of fluid and said lockingmeans being releasable upon initial movement of the piston in thedirection of compression, said piston having an internal recess, meansproviding restricted communication between the recess and the casingwhereby to permit fluid to gain access to the recess, and meansproviding a closed com pressible chamber located within the said recessand responsive to displacement of the fluid for permitting displacementof the fluid in the casing upon movement of the piston away from itslocked position whereby to facilitate release ,of the locking means.

preventing rotation of the connected piston and valve from aninoperative position preventing distribution of the fluid and saidlocking means .being releasable upon initial movement of the piston inthe direction of compression, means providing an internal recess withinthe piston and said recess being in communication with the pump casing,and means disposed within said recess and responsive to fluid pressurefor per mitting displacement of the fluid in the casing upon movement ofthe piston away from its locked position whereby to facilitate releaseof the locking means.

6. A fluid dispensing device comprising a pump casing having areciprocating piston therein, a distributing valve associated with thecasing for controlling distribution of the fluid, means operable toprovide a releasable connection between the piston and valve foreffecting rotation of the valve to various set positions upon rotationof the piston but permitting reciprocation, of the piston independentlyof the valve, and means providing a variable chamber associated with thedispensing device and responsive to displacement of fluid within thecasing for permitting displacement of the fluid and the piston toward aposition for rotating the valve to predetermined set positions,

'7. A fluid dispensing device comprising a pump casing having areciprocating piston therein, a distributing valve associated with thecasing for controlling distribution of the fluid, means operable toprovide a releasable connection between the piston and the valve nearthe end of the compression stroke of the piston whereby rotation of thepiston will effect rotation of the valve to various set positions,locking means for pre- .piston away from its locked position whereby tofacilitate release of the locking means.

8. A fluid dispensing device comprising a pump casing having areciprocating piston therein, a valve housing associated with the casingand having a distributing valve therein for controlling distribution ofthe fluid, a check valve controlling the inlet to the valve housing andpermitting admission of fluid on the suction stroke of the piston butpreventing discharge of the fluid through the inlet on the compressionstroke of the piston, means operable to provide a releasable connectionbetween the piston and the valve near the end of the compression strokeof the piston whereby rotation of the piston will effect rotation of thevalve to different set positions, locking means for preventing rotationof the connected piston and valve from an inoperative positionpreventing distribution of fluid and said locking means being releasableupon initial movement of the piston in the direction of compression, andmeans providing a variable chamber associated with the dispensing deviceand operable in the event that the fluid is under sufficiently highpressure to fill the casing by opening the check valve at the inlet tothe valve housing for permitting limited displacement of the fluid inthe casing upon movement of the piston away from its locked positionwhereby to facilitate release of the locking means.

9. A fluid dispensing device comprising a pump casing having areciprocating piston therein, a distributing valve associated with thecasing for controlling distribution of the fluid, means operable toprovide a releasable connection between the piston and the valve nearthe end of the compression stroke of the piston whereby rotation of thepiston-will effect rotation of the valve to various set positions,locking means for preventing rotation of the connected piston and valvefrom an inoperative position preventing distribution of fluid and saidlocking means being releasable upon initial movement of the piston inthe direction of compression, and means disposed within the piston andproviding a variable chamber connected with the dispensing device andoperable in the event that the casing is filled with fluid to permitlimited displacement of the fluid upon movement of the piston away fromits locked position whereby to facilitate release of the lockmg means.

- ARTHUR L. PARKER.

